1. Field of the Invention
The present invention relates to assembling of a vapor-deposited metal film capacitor module used in a winding-type or laminated-type film capacitor device, and more particularly to a bus-bar for assembling a capacitor device, capable of improving the environment of a soldering operation for the bus-bar being soldered to a capacitor device, reducing the inferior rate of the capacitor device while improving the quality of the capacitor device, and reducing the weight of the capacitor module, when forming respective cathode and anode terminals by uniting the same polarities of a plurality of capacitor devices through the bus-bar to modularize the plurality of capacitor devices.
2. Description of the Related Art
In general, electric equipment capacitor devices, phase-advanced capacitor devices and electronic equipment capacitor devices are used in a variety of industrial fields. In the capacitor device, a plastic film such as Polyethylene terephthalate resin, polypropylene resin, polyethylene naphthalate resin, polycarbonate resin and the like is used as a dielectric. The capacitor device is fabricated by winding a vapor-deposited metal film on either or both sides of the plastic film and forming electrodes using Zn or a Zn alloy at both sides of the wound vapor-deposited film. One or more capacitor devices are connected by spot-welding or soldering an electrode lead wire, a bus-bar, or a terminal. The connected capacitor devices are housed in an outer case and then insulated by charging a space between the respective capacitor devices and the outer case with an insulating material such as epoxy. Thus, the capacitor devices are modularized.
As shown in FIG. 1 and FIG. 2, the modularized capacitor device assembly is exposed to the outside only by a terminal 5 of a bus-bar 10 electrically connected with polar plates 1a and 1b of a capacitor device 1. The bus-bar terminal 5 becomes a polar element connected with a cable or another bus-bar (not shown).
The bus-bar 10 according to the conventional art includes oval or circular holes 11 having about a 10 mm diameter on the surface thereof. A lead frame 12 for soldering is formed on a circumference of the hole 11. The holes 11 are formed to correspond to the capacitor devices 1 one by one.
However, in the bus-bar 10 wherein the capacitor devices 1 and the holes 11 are provided corresponding to each other, during the soldering, it is hard for an iron tip to contact the polar plates 1a and 1b of the capacitor device 1 by interference with the hole 11 having such a small diameter. Or, heat of the lead frame 12 may be transmitted to a surface of the bus-bar 10. In this case, although solder is melted, the melted solder is not easily welded into the lead frame 12 and the polar plates 1a and 1b, thereby frequently causing poor bonding.
This is because a thick material is generally used for the bus-bar 10 so that the bus-bar 10 has an enough capacity for the current flowing in the capacitor device 1. Therefore, whereas it takes a long time to increase temperature of the lead frame 12, the solder having a low melting point is very rapidly melted. That is, the poor bonding is incurred due to the time-lag in melting between the different materials.
For this reason, the bus-bar 10 has been soldered and bonded by an operator's manual operation as described above. However, the holes 11 formed on the surface of the bus-bar 10 are too small to conveniently perform the soldering. In addition, the operator has to examine places of the poor bonding one by one, the poor bonding occurring between the capacitor device 1 and the bus-bar 10 due to the time-lag in melting between the different materials. Furthermore, a surface area of the bus-bar 10 increases according to increase of the number of capacitor devices 1, thereby increasing the whole weight of the capacitor module.
In the bus-bar 10 connected to the capacitor device 1 at a rear part of the outer case C, as a bent plate 10a being bent to be parallel with a lateral side of the capacitor device 1 is brought in contact with the outer case C of the capacitor device 1, the rear polar plate 1a and the front polar plate 1b may be applied with electricity, that is, a short circuit at two terminals 5 may frequently be caused by the outer case 1 of the capacitor device 1. To explain the reason of the short circuit more specifically, when spraying of metal is performed to form the polar plates 1a and 1b of the capacitor device 1, the outer case C is stained with part of the metal being sprayed. In addition, since the soldering is performed by the manual operation, the soldering position of the lead frame 12 of the bus-bar 10 soldered to the polar plates 1a and 1b becomes all different according to the operator. Accordingly, an interval between the outer case C of the capacitor device 1 and the bus-bar 10 is irregular.
Therefore, after the capacitor device 1 attached with the bus-bar 10 is housed in the outer case C and the epoxy is injected in between the bent plate 10a and an outer cover 1c, the injection is not smoothly performed, thereby generating a space. The bus-bar 10 and the outer cover 1c electrically contact each other in the space, thereby causing the short circuit.